At the moment optimizer does window function materialization even if join produces no rows:
create or replace table t1 (a int, b int, c int, index(a, b, c));
|
create or replace table t2 (a int, b int, c int, index(a, b, c));
|
|
insert into t1 select seq, seq, seq from seq_1_to_500000;
|
insert into t2 select seq, seq, seq from seq_1_to_500000;
|
|
explain
|
select * from
|
(
|
select t1.a a, t2.b b, t2.c, sum(t2.c) over ( partition by a,b,c )
|
from t1 join t2
|
where
|
t1.a=t2.a and t1.b=t2.b
|
) v1 join ( select 1000000 as a, 1000000 as b, 1000000 as c ) v2 using (a,b,c);
|
+------+-------------+------------+--------+---------------+------+---------+---------------------+--------+-------------------------------------------+
|
| id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra |
|
+------+-------------+------------+--------+---------------+------+---------+---------------------+--------+-------------------------------------------+
|
| 1 | PRIMARY | <derived3> | system | NULL | NULL | NULL | NULL | 1 | |
|
| 1 | PRIMARY | <derived2> | ref | key0 | key0 | 15 | const,const,const | 10 | |
|
| 3 | DERIVED | NULL | NULL | NULL | NULL | NULL | NULL | NULL | No tables used |
|
| 2 | DERIVED | t1 | index | a | a | 15 | NULL | 500000 | Using where; Using index; Using temporary |
|
| 2 | DERIVED | t2 | ref | a | a | 10 | test.t1.a,test.t1.b | 1 | Using index |
|
+------+-------------+------------+--------+---------------+------+---------+---------------------+--------+-------------------------------------------+
|
MariaDB [test]> select count(*) from
|
-> (
|
-> select t1.a a, t2.b b, t2.c, sum(t2.c) over ( partition by a,b,c )
|
-> from t1 join t2
|
-> where
|
-> t1.a=t2.a and t1.b=t2.b
|
-> ) v1 join ( select 1000000 as a, 1000000 as b, 1000000 as c ) v2 using (a,b,c);
|
+----------+
|
| count(*) |
|
+----------+
|
| 0 |
|
+----------+
|
1 row in set (2.27 sec)
|
For good performance it is required to skip materialization at all if no rows are joined and try to push condition if only few rows are joined like in MDEV-13385
- relates to
-
MDEV-13385
Window Functions: Push condition into inner query
-
-
Closed
{"report":{"fcp":1423.5,"ttfb":380.90000009536743,"pageVisibility":"visible","entityId":62402,"key":"jira.project.issue.view-issue","isInitial":true,"threshold":1000,"elementTimings":{},"userDeviceMemory":8,"userDeviceProcessors":32,"apdex":0.5,"journeyId":"f8013c5d-9179-450f-ac88-81ed2d3d4a2d","navigationType":0,"readyForUser":1517.9000000953674,"redirectCount":0,"resourceLoadedEnd":1945.8000001907349,"resourceLoadedStart":386.40000009536743,"resourceTiming":[{"duration":342.19999980926514,"initiatorType":"link","name":"https://jira.mariadb.org/s/2c21342762a6a02add1c328bed317ffd-CDN/lu2cib/820016/12ta74/0a8bac35585be7fc6c9cc5a0464cd4cf/_/download/contextbatch/css/_super/batch.css","startTime":386.40000009536743,"connectEnd":0,"connectStart":0,"domainLookupEnd":0,"domainLookupStart":0,"fetchStart":386.40000009536743,"redirectEnd":0,"redirectStart":0,"requestStart":0,"responseEnd":728.5999999046326,"responseStart":0,"secureConnectionStart":0},{"duration":342.2999997138977,"initiatorType":"link","name":"https://jira.mariadb.org/s/7ebd35e77e471bc30ff0eba799ebc151-CDN/lu2cib/820016/12ta74/494e4c556ecbb29f90a3d3b4f09cb99c/_/download/contextbatch/css/jira.browse.project,project.issue.navigator,jira.view.issue,jira.general,jira.global,atl.general,-_super/batch.css?agile_global_admin_condition=true&jag=true&jira.create.linked.issue=true&slack-enabled=true&whisper-enabled=true","startTime":386.80000019073486,"connectEnd":0,"connectStart":0,"domainLookupEnd":0,"domainLookupStart":0,"fetchStart":386.80000019073486,"redirectEnd":0,"redirectStart":0,"requestStart":0,"responseEnd":729.0999999046326,"responseStart":0,"secureConnectionStart":0},{"duration":351.40000009536743,"initiatorType":"script","name":"https://jira.mariadb.org/s/0917945aaa57108d00c5076fea35e069-CDN/lu2cib/820016/12ta74/0a8bac35585be7fc6c9cc5a0464cd4cf/_/download/contextbatch/js/_super/batch.js?locale=en","startTime":386.90000009536743,"connectEnd":386.90000009536743,"connectStart":386.90000009536743,"domainLookupEnd":386.90000009536743,"domainLookupStart":386.90000009536743,"fetchStart":386.90000009536743,"redirectEnd":0,"redirectStart":0,"requestStart":386.90000009536743,"responseEnd":738.3000001907349,"responseStart":738.3000001907349,"secureConnectionStart":386.90000009536743},{"duration":418,"initiatorType":"script","name":"https://jira.mariadb.org/s/2d8175ec2fa4c816e8023260bd8c1786-CDN/lu2cib/820016/12ta74/494e4c556ecbb29f90a3d3b4f09cb99c/_/download/contextbatch/js/jira.browse.project,project.issue.navigator,jira.view.issue,jira.general,jira.global,atl.general,-_super/batch.js?agile_global_admin_condition=true&jag=true&jira.create.linked.issue=true&locale=en&slack-enabled=true&whisper-enabled=true","startTime":387,"connectEnd":387,"connectStart":387,"domainLookupEnd":387,"domainLookupStart":387,"fetchStart":387,"redirectEnd":0,"redirectStart":0,"requestStart":387,"responseEnd":805,"responseStart":805,"secureConnectionStart":387},{"duration":422.09999990463257,"initiatorType":"script","name":"https://jira.mariadb.org/s/a9324d6758d385eb45c462685ad88f1d-CDN/lu2cib/820016/12ta74/c92c0caa9a024ae85b0ebdbed7fb4bd7/_/download/contextbatch/js/atl.global,-_super/batch.js?locale=en","startTime":387.30000019073486,"connectEnd":387.30000019073486,"connectStart":387.30000019073486,"domainLookupEnd":387.30000019073486,"domainLookupStart":387.30000019073486,"fetchStart":387.30000019073486,"redirectEnd":0,"redirectStart":0,"requestStart":387.30000019073486,"responseEnd":809.4000000953674,"responseStart":809.4000000953674,"secureConnectionStart":387.30000019073486},{"duration":422.5,"initiatorType":"script","name":"https://jira.mariadb.org/s/d41d8cd98f00b204e9800998ecf8427e-CDN/lu2cib/820016/12ta74/1.0/_/download/batch/jira.webresources:calendar-en/jira.webresources:calendar-en.js","startTime":387.40000009536743,"connectEnd":387.40000009536743,"connectStart":387.40000009536743,"domainLookupEnd":387.40000009536743,"domainLookupStart":387.40000009536743,"fetchStart":387.40000009536743,"redirectEnd":0,"redirectStart":0,"requestStart":387.40000009536743,"responseEnd":809.9000000953674,"responseStart":809.9000000953674,"secureConnectionStart":387.40000009536743},{"duration":422.7000002861023,"initiatorType":"script","name":"https://jira.mariadb.org/s/d41d8cd98f00b204e9800998ecf8427e-CDN/lu2cib/820016/12ta74/1.0/_/download/batch/jira.webresources:calendar-localisation-moment/jira.webresources:calendar-localisation-moment.js","startTime":387.59999990463257,"connectEnd":387.59999990463257,"connectStart":387.59999990463257,"domainLookupEnd":387.59999990463257,"domainLookupStart":387.59999990463257,"fetchStart":387.59999990463257,"redirectEnd":0,"redirectStart":0,"requestStart":387.59999990463257,"responseEnd":810.3000001907349,"responseStart":810.3000001907349,"secureConnectionStart":387.59999990463257},{"duration":525.6999998092651,"initiatorType":"link","name":"https://jira.mariadb.org/s/b04b06a02d1959df322d9cded3aeecc1-CDN/lu2cib/820016/12ta74/a2ff6aa845ffc9a1d22fe23d9ee791fc/_/download/contextbatch/css/jira.global.look-and-feel,-_super/batch.css","startTime":387.80000019073486,"connectEnd":0,"connectStart":0,"domainLookupEnd":0,"domainLookupStart":0,"fetchStart":387.80000019073486,"redirectEnd":0,"redirectStart":0,"requestStart":0,"responseEnd":913.5,"responseStart":0,"secureConnectionStart":0},{"duration":422.80000019073486,"initiatorType":"script","name":"https://jira.mariadb.org/rest/api/1.0/shortcuts/820016/47140b6e0a9bc2e4913da06536125810/shortcuts.js?context=issuenavigation&context=issueaction","startTime":388,"connectEnd":388,"connectStart":388,"domainLookupEnd":388,"domainLookupStart":388,"fetchStart":388,"redirectEnd":0,"redirectStart":0,"requestStart":388,"responseEnd":810.8000001907349,"responseStart":810.8000001907349,"secureConnectionStart":388},{"duration":525.7000002861023,"initiatorType":"link","name":"https://jira.mariadb.org/s/3ac36323ba5e4eb0af2aa7ac7211b4bb-CDN/lu2cib/820016/12ta74/d176f0986478cc64f24226b3d20c140d/_/download/contextbatch/css/com.atlassian.jira.projects.sidebar.init,-_super,-project.issue.navigator,-jira.view.issue/batch.css?jira.create.linked.issue=true","startTime":388.09999990463257,"connectEnd":0,"connectStart":0,"domainLookupEnd":0,"domainLookupStart":0,"fetchStart":388.09999990463257,"redirectEnd":0,"redirectStart":0,"requestStart":0,"responseEnd":913.8000001907349,"responseStart":0,"secureConnectionStart":0},{"duration":423.09999990463257,"initiatorType":"script","name":"https://jira.mariadb.org/s/5d5e8fe91fbc506585e83ea3b62ccc4b-CDN/lu2cib/820016/12ta74/d176f0986478cc64f24226b3d20c140d/_/download/contextbatch/js/com.atlassian.jira.projects.sidebar.init,-_super,-project.issue.navigator,-jira.view.issue/batch.js?jira.create.linked.issue=true&locale=en","startTime":388.30000019073486,"connectEnd":388.30000019073486,"connectStart":388.30000019073486,"domainLookupEnd":388.30000019073486,"domainLookupStart":388.30000019073486,"fetchStart":388.30000019073486,"redirectEnd":0,"redirectStart":0,"requestStart":388.30000019073486,"responseEnd":811.4000000953674,"responseStart":811.4000000953674,"secureConnectionStart":388.30000019073486},{"duration":697.0999999046326,"initiatorType":"script","name":"https://jira.mariadb.org/s/d41d8cd98f00b204e9800998ecf8427e-CDN/lu2cib/820016/12ta74/1.0/_/download/batch/jira.webresources:bigpipe-js/jira.webresources:bigpipe-js.js","startTime":398.80000019073486,"connectEnd":398.80000019073486,"connectStart":398.80000019073486,"domainLookupEnd":398.80000019073486,"domainLookupStart":398.80000019073486,"fetchStart":398.80000019073486,"redirectEnd":0,"redirectStart":0,"requestStart":398.80000019073486,"responseEnd":1095.9000000953674,"responseStart":1095.8000001907349,"secureConnectionStart":398.80000019073486},{"duration":1543.1999998092651,"initiatorType":"script","name":"https://jira.mariadb.org/s/d41d8cd98f00b204e9800998ecf8427e-CDN/lu2cib/820016/12ta74/1.0/_/download/batch/jira.webresources:bigpipe-init/jira.webresources:bigpipe-init.js","startTime":398.90000009536743,"connectEnd":398.90000009536743,"connectStart":398.90000009536743,"domainLookupEnd":398.90000009536743,"domainLookupStart":398.90000009536743,"fetchStart":398.90000009536743,"redirectEnd":0,"redirectStart":0,"requestStart":398.90000009536743,"responseEnd":1942.0999999046326,"responseStart":1942.0999999046326,"secureConnectionStart":398.90000009536743},{"duration":133.2000002861023,"initiatorType":"xmlhttprequest","name":"https://jira.mariadb.org/rest/webResources/1.0/resources","startTime":963,"connectEnd":963,"connectStart":963,"domainLookupEnd":963,"domainLookupStart":963,"fetchStart":963,"redirectEnd":0,"redirectStart":0,"requestStart":963,"responseEnd":1096.2000002861023,"responseStart":1096.2000002861023,"secureConnectionStart":963},{"duration":628.4000000953674,"initiatorType":"link","name":"https://jira.mariadb.org/s/d5715adaadd168a9002b108b2b039b50-CDN/lu2cib/820016/12ta74/be4b45e9cec53099498fa61c8b7acba4/_/download/contextbatch/css/jira.project.sidebar,-_super,-project.issue.navigator,-jira.general,-jira.browse.project,-jira.view.issue,-jira.global,-atl.general,-com.atlassian.jira.projects.sidebar.init/batch.css?agile_global_admin_condition=true&jag=true&jira.create.linked.issue=true&slack-enabled=true&whisper-enabled=true","startTime":1314.5,"connectEnd":0,"connectStart":0,"domainLookupEnd":0,"domainLookupStart":0,"fetchStart":1314.5,"redirectEnd":0,"redirectStart":0,"requestStart":0,"responseEnd":1942.9000000953674,"responseStart":0,"secureConnectionStart":0},{"duration":622,"initiatorType":"script","name":"https://jira.mariadb.org/s/d41d8cd98f00b204e9800998ecf8427e-CDN/lu2cib/820016/12ta74/e65b778d185daf5aee24936755b43da6/_/download/contextbatch/js/browser-metrics-plugin.contrib,-_super,-project.issue.navigator,-jira.view.issue,-atl.general/batch.js?agile_global_admin_condition=true&jag=true&jira.create.linked.issue=true&slack-enabled=true&whisper-enabled=true","startTime":1321.5,"connectEnd":1321.5,"connectStart":1321.5,"domainLookupEnd":1321.5,"domainLookupStart":1321.5,"fetchStart":1321.5,"redirectEnd":0,"redirectStart":0,"requestStart":1321.5,"responseEnd":1943.5,"responseStart":1943.5,"secureConnectionStart":1321.5},{"duration":623.9000000953674,"initiatorType":"script","name":"https://jira.mariadb.org/s/097ae97cb8fbec7d6ea4bbb1f26955b9-CDN/lu2cib/820016/12ta74/be4b45e9cec53099498fa61c8b7acba4/_/download/contextbatch/js/jira.project.sidebar,-_super,-project.issue.navigator,-jira.general,-jira.browse.project,-jira.view.issue,-jira.global,-atl.general,-com.atlassian.jira.projects.sidebar.init/batch.js?agile_global_admin_condition=true&jag=true&jira.create.linked.issue=true&locale=en&slack-enabled=true&whisper-enabled=true","startTime":1321.9000000953674,"connectEnd":1321.9000000953674,"connectStart":1321.9000000953674,"domainLookupEnd":1321.9000000953674,"domainLookupStart":1321.9000000953674,"fetchStart":1321.9000000953674,"redirectEnd":0,"redirectStart":0,"requestStart":1321.9000000953674,"responseEnd":1945.8000001907349,"responseStart":1945.8000001907349,"secureConnectionStart":1321.9000000953674},{"duration":556.3000001907349,"initiatorType":"script","name":"https://www.google-analytics.com/analytics.js","startTime":1409.9000000953674,"connectEnd":0,"connectStart":0,"domainLookupEnd":0,"domainLookupStart":0,"fetchStart":1409.9000000953674,"redirectEnd":0,"redirectStart":0,"requestStart":0,"responseEnd":1966.2000002861023,"responseStart":0,"secureConnectionStart":0}],"fetchStart":0,"domainLookupStart":0,"domainLookupEnd":0,"connectStart":0,"connectEnd":0,"requestStart":209,"responseStart":381,"responseEnd":398,"domLoading":385,"domInteractive":2097,"domContentLoadedEventStart":2097,"domContentLoadedEventEnd":2228,"domComplete":4459,"loadEventStart":4459,"loadEventEnd":4462,"userAgent":"Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)","marks":[{"name":"bigPipe.sidebar-id.start","time":1952},{"name":"bigPipe.sidebar-id.end","time":1952.9000000953674},{"name":"bigPipe.activity-panel-pipe-id.start","time":1953.2000002861023},{"name":"bigPipe.activity-panel-pipe-id.end","time":1956.5},{"name":"activityTabFullyLoaded","time":2251}],"measures":[],"correlationId":"2f084abea9a8e5","effectiveType":"4g","downlink":9.5,"rtt":0,"serverDuration":98,"dbReadsTimeInMs":12,"dbConnsTimeInMs":22,"applicationHash":"9d11dbea5f4be3d4cc21f03a88dd11d8c8687422","experiments":[]}}